U.S. patent number 6,064,858 [Application Number 08/945,465] was granted by the patent office on 2000-05-16 for ground-station system, ground station, device, method.
This patent grant is currently assigned to Koninklijke PTT Nederland N.V.. Invention is credited to Johannes Jozeph Maatman, Peter Zijlema.
United States Patent |
6,064,858 |
Maatman , et al. |
May 16, 2000 |
Ground-station system, ground station, device, method
Abstract
Known ground-station systems offer users of mobile stations a
different standard procedure for each ground station. By
through-coupling an aerial of the ground station to a processing
arrangement of the ground station in response to a first
identification code, satellite signals comprising the first
identification code being processed via the processing arrangement
of the ground station, and by through-coupling the aerial via a
link to another processing arrangement of another ground station in
response to a second identification code, satellite signals
comprising the second identification code not being processed via
the processing arrangement of the ground station, but only being
transmitted by the ground station via the link to the other
processing arrangement of the other ground station in order to be
processed subsequently by the other processing arrangement at the
site of the other ground station, the result is achieved that a
user of a mobile station deals with one standard procedure over the
entire world and a "global image" is created.
Inventors: |
Maatman; Johannes Jozeph (The
Hague, NL), Zijlema; Peter (Warmond, NL) |
Assignee: |
Koninklijke PTT Nederland N.V.
(NL)
|
Family
ID: |
19761202 |
Appl.
No.: |
08/945,465 |
Filed: |
November 13, 1997 |
PCT
Filed: |
June 10, 1996 |
PCT No.: |
PCT/EP96/02534 |
371
Date: |
November 13, 1997 |
102(e)
Date: |
November 13, 1997 |
PCT
Pub. No.: |
WO97/01225 |
PCT
Pub. Date: |
January 09, 1997 |
Foreign Application Priority Data
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Jun 22, 1995 [NL] |
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1000628 |
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Current U.S.
Class: |
455/12.1;
455/427 |
Current CPC
Class: |
H04B
7/18517 (20130101) |
Current International
Class: |
H04B
7/185 (20060101); H04B 007/185 () |
Field of
Search: |
;455/12.1,13.1,13.2,427,428,429,412,414,433,445 |
References Cited
[Referenced By]
U.S. Patent Documents
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5070537 |
December 1991 |
Ohira et al. |
5509004 |
April 1996 |
Bishop, Jr. et al. |
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Foreign Patent Documents
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2275588A |
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Aug 1994 |
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GB |
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WO 92/00636 |
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Jan 1992 |
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WO |
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WO 92/19050 |
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Oct 1992 |
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WO |
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Primary Examiner: Vo; Nguyen
Assistant Examiner: Bhattacharya; Sam
Attorney, Agent or Firm: Michaelson & Wallace
Michaelson; Peter L.
Claims
What is claimed is:
1. A ground-station system comprising:
a first ground station having:
a first aerial for reception of a first satellite signal comprising
an identification code and a destination code;
a first processing arrangement having a first input, coupled to the
first aerial, for reception and processing of the first satellite
signal and having a first output for generation of a first outgoing
signal; and
a first detection arrangement, operative in conjunction with the
first processing arrangement, for detecting the identification
code; and
a second ground station having:
a second aerial for reception of a second satellite signal
comprising an identification code;
a second processing arrangement having a second input, coupled to
the second aerial, for reception and processing of the second
satellite signal and having a second output for generation of a
second output signal; and
a second detection arrangement, operative in conjunction with the
second processing arrangement, for detecting the identification
code; and
wherein:
the first detection arrangement comprises a first through-coupling
arrangement for through-coupling the first aerial to the first
processing arrangement in response to the identification code being
a first type and for through-coupling the first aerial to a further
second input of the second processing arrangement via a first link
in response to the identification code being a second type; and
the first ground station further comprises:
a further first detection arrangement for detecting the destination
code; and
a further first through-coupling arrangement, responsive to the
further first detection arrangement, for through-coupling the first
aerial to the first processing arrangement in response to the
destination code being a first type and for through-coupling the
first aerial to the further second input of the second processing
arrangement via the first link in response to the destination code
being a second type.
2. The ground-station system according to claim 1, wherein:
the second detection arrangement comprises a second
through-coupling arrangement for through-coupling the second aerial
to the second processing arrangement in response to the
identification code being the second type and for through-coupling
the second aerial to a further first input of the first processing
arrangement via a second link in response to the identification
code being the a first type; and
the second ground station further comprises:
a further second detection arrangement for detecting the
destination code; and
a further second through-coupling arrangement, responsive to the
further second detection arrangement, for through-coupling the
second aerial to the second processing arrangement in response to
the destination code being the first type and for through-coupling
the second aerial to the further second input of the first
processing arrangement via the second link in response to the
destination code being the second type.
3. A ground-station system comprising
a first ground station having:
a first aerial for reception of a first satellite signal comprising
an identification code;
a first processing arrangement having a first input, coupled to the
first aerial, for reception and processing of the first satellite
signal and having a first output for generation of a first outgoing
signal; and
a first detection arrangement, operative in conjunction with the
first processing arrangement, for detecting the identification
code; and
a second ground station having:
a second aerial for reception of a second satellite signal
comprising an identification code and a destination code;
a second processing arrangement having a second input, coupled to
the second aerial, for reception and processing of the second
satellite signal and having a second output for generation of a
second output signal; and
a second detection arrangement, operative in conjunction with the
second processing arrangement, for detecting the identification
code; and
wherein:
the first detection arrangement comprises a first through-coupling
arrangement for through-coupling the first aerial to the first
processing arrangement in response to the identification code being
a first type and for through-coupling the first aerial to a further
second input of the second processing arrangement via a first link
in response to the identification code being a second type;
the second detection arrangement comprises a second
through-coupling arrangement for through-coupling the second aerial
to the second processing arrangement in response to the
identification code being the second type and for through-coupling
the second aerial to a further first input of the first processing
arrangement via a second link in response to the identification
code being the first type; and
the second ground station further comprises:
a further second detection arrangement for detecting the
destination code; and
a further second through-coupling arrangement for through-coupling
the second aerial to the second processing arrangement in response
to the destination code being a first type and for through-coupling
the second aerial to the further second input of the first
processing arrangement via
the second link in response to the destination code being a second
type.
4. A ground station, for use in a ground station system,
comprising:
an aerial for reception of a satellite signal comprising an
identification code and a destination code;
a processing arrangement comprising an input, coupled to the
aerial, for reception and processing of the satellite signal and
having an output for generating a first outgoing signal;
a detection arrangement, operative in conjunction with the
processing arrangement, for detecting the identification code,
wherein the detection arrangement comprises a through-coupling
arrangement for through-coupling the aerial to the processing
arrangement in response to the identification code being a first
type and for through-coupling the aerial to a link coupled to a
further ground station for feeding a portion of the satellite
signal to said further ground station in response to the
identification code being a second type;
a further detection arrangement for detecting the destination code;
and
a further through-coupling arrangement, responsive to the further
detection arrangement, for through-coupling the aerial to the
processing arrangement in response to the destination code being a
first type and for through-coupling the aerial to the link coupled
to the further ground station in response to the destination code
being a second type.
5. A device for use in a ground station which is provided with an
aerial for reception of a satellite signal comprising an
identification code and a destination code, wherein the device
comprises:
processing arrangement having an input which can be coupled to the
aerial for reception and processing of the satellite signal and
having an output for generating a first outgoing signal;
a detection arrangement, operative in conjunction with the
processing arrangement, for detecting the identification code,
wherein the detection arrangement has a through-coupling
arrangement for through-coupling the aerial to the processing
arrangement in response to the identification code being a first
type and for through-coupling the aerial to a link coupled to a
further ground station for feeding a portion of the satellite
signal to said further ground station in response to the
identification code being a second type;
a further detection arrangement for detecting the destination code;
and
a further through-coupling arrangement, responsive to the further
detection arrangement, for through-coupling the aerial to the
processing arrangement in response to the destination code being a
first type and for through-coupling the aerial to the link coupled
to the further ground station in response to the destination code
being a second type.
6. A method for processing a satellite signal originating from a
satellite by a ground station, wherein the method comprises the
steps of:
receiving the satellite signal, having an identification code and a
destination code, via an aerial of the ground station so as to
define a received satellite signal;
feeding the received satellite signal to a processing arrangement
of the ground station;
processing the received satellite signal by the processing
arrangement of the ground station and generating a first outgoing
signal;
detecting the identification code by a detection arrangement of the
ground station;
through-coupling the aerial of the ground station to the processing
arrangement of the ground station in order to process the satellite
signal via the processing arrangement of the ground station in
response to the identification code being a first type; and
through-coupling the aerial of the ground station to a link coupled
to a further ground station for feeding a portion of the satellite
signal to said further ground station in order to process the
portion of the satellite signal via a further processing
arrangement of the further ground station in response to the
identification code being a second type;
detecting the destination code associated with the satellite signal
by a further detection arrangement of the ground station;
through-coupling the aerial of the ground station to the processing
arrangement of the ground station in order to process the satellite
signal via the processing arrangement of the ground station in
response to the destination code being a first type; and
through-coupling the aerial of the ground station to the link
coupled to the further ground station for feeding the portion of
the satellite signal to said further ground station in order to
process the portion of the satellite signal via the further
processing arrangement of the further ground station in response to
the destination code being a second type.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a ground-station system comprising a first
ground station which is provided with
at least one first aerial for the reception of a first satellite
signal comprising an identification code,
a first processing arrangement comprising a first input, coupled to
the first aerial, for the reception and processing of the first
satellite signal and comprising a first output for the generation
of a first outgoing signal, and
a first detection arrangement for detecting the identification
code, and comprising a second ground station which is provided
with
at least one second aerial for the reception of a second satellite
signal comprising an identification code,
a second processing arrangement comprising a second input, coupled
to the second aerial, for the reception and processing of the
second satellite signal and comprising a second output for the
generation of a second outgoing signal, and
a second detection arrangement for detecting the identification
code.
2. Description of the Prior Art
Such a ground-station system is generally known and makes use, for
example, of four satellites which are each situated at such a
height above the earth's surface and are each situated at such a
degree of longitude and degree of latitude that an attempt can be
made to contact at least one of the four satellites from virtually
any terrestrial location, and in which the total of the four
satellites can try to contact with virtually any terrestrial
location. From certain terrestrial locations, of course, contact
can be sought with more than one satellite, such as two or even
three satellites, and preferably, a ground station will be sited at
such a certain location.
The first ground station of a first operator is then situated in a
first country and can try to contact, for example, the first,
second and third satellite, the first ground station then having
control over three first aerials. A first mobile station situated
within the range of the first, second or third satellite in that
case transmits the first satellite signal comprising a first
identification code, such as, for example, a first ground-station
identification code, to the first, second or third satellite which
passes the first satellite signal comprising the first
ground-station identification code, to the first ground station.
The first satellite signal, comprising the first ground-station
identification code and received via one of the three first
aerials, is processed via the first processing arrangement, in
response to which the first outgoing signal is generated. Under
these circumstances, the first detection arrangement detects said
first ground-station identification code, from which it then
emerges that the first satellite signal, comprising the first
ground-station identification code, is intended for the first
ground station.
The second ground station of a second operator is then situated in
a second country and can try to contact, for example, the third and
fourth satellite, the second ground station then having control
over two second aerials. A second mobile station situated within
the range of the third or fourth satellite in that case transmits
the second satellite signal, comprising a second identification
code, such as, for example, a second ground-station identification
code, to the third or fourth satellite which passes the second
satellite signal, comprising the second ground-station
identification code, to the second ground station. The second
satellite signal, comprising the second ground-station
identification code and received via one of the two second aerials,
is processed via the second processing arrangement, in response to
which the second outgoing signal is generated. Under these
circumstances, the second detection arrangement detects the second
ground-station identification code, from which it then emerges that
the second satellite signal, comprising the second ground-station
identification code, is intended for the second ground station.
If the user with his mobile station is situated, for example,
within the range of the third satellite, he can generate either the
first satellite signal, comprising the first ground-station
identification code, or the second satellite signal, comprising the
second ground-station identification code. In this case, the first
ground station then responds, after detecting the first
ground-station identification code, to the first satellite signal
and the second ground station responds, after detecting the second
ground-station identification code, to the second satellite signal.
On the other hand, if the user with his mobile station is situated,
for example, within the range of the fourth satellite, he must
generate per se the second satellite signal, comprising the second
ground-station identification code, in which case the second ground
station responds, after detecting the second ground-station
identification code, to said second satellite signal.
Such a ground-station system has, inter alia, the disadvantage that
a user of a mobile station cannot manage according to one standard
procedure over the entire world, but has to deal instead with a
standard procedure which is different for each ground station.
SUMMARY OF THE INVENTION
The object of the invention is, inter alia, to provide a
ground-station system of the type mentioned in the introduction, in
which a user of a mobile station has to deal with one standard
procedure over the entire world.
For this purpose, the ground-station system according to the
invention has the characteristic that the first detection
arrangement is provided with a first through-coupling arrangement
for through-coupling the first aerial to the first processing
arrangement in response to an identification code of a first type
and for through-coupling the first aerial to a further second input
of the second processing arrangement via a first link in response
to an identification code of a second type.
By providing the first detection arrangement with the first
through-coupling arrangement which through-couples the first aerial
to the first processing arrangement in response to the
identification code of the first type (such as, for example, the
ground-station identification code of the first type) and which
through-couples the first aerial to the further second input of the
second processing arrangement via the first link in response to the
identification code of the second type (such as, for example, the
ground-station identification code of the second type), the result
is achieved that, if the first ground station situated in a first
country responds to first satellite signals, comprising the
identification code of the first type (such as, for example, the
ground-station identification code of the first type), the first
satellite signals are consequently also actually processed via the
first processing arrangement of the first ground station, whereas,
if the first ground station responds to first satellite signals,
comprising the identification code of the second type (such as, for
example, the ground-station identification code of the second
type), the first satellite signals, are not processed via the first
processing arrangement of the first ground station, but are only
transmitted by the first ground station via the first link to the
second processing arrangement of the second ground station situated
in a second country in order to be processed subsequently by the
second processing arrangement at the site of the second ground
station. In this case, the first link between the first ground
station and the second ground station is a communication connection
which can be formed, for example, by means of copper connections
and/or glass-fiber connections and/or satellite connections and/or
terrestrial radio connections.
The invention is based, inter alia, on the insight that, regardless
of whether they comprise identification codes, such as, for
example, ground-station identification codes, of the first or the
second type, message-switched satellite signals, for example, can
be received via a first aerial of a first ground station, in which
case said satellite signals should generally be processed at the
site of the first ground station if they comprise identification
codes of the first type (such as, for example, ground-station
identification codes of the first type), whereas the satellite
signals can generally be transmitted without processing at the site
of the first ground station via the first link to the second ground
station in order to be processed there at the site, if they
comprise identification codes of the second type (such as, for
example, ground-station identification codes of the second
type).
The problem of the user of a mobile station having to deal with a
different standard procedure for each ground station is solved by
processing the satellite signals either directly after reception at
the site of a first ground station or indirectly after reception by
the first ground station and after transmission to, and reception
by, a second ground station at the site of the latter, depending on
an identification code to be detected, such as, for example, a
ground-station identification code.
Further advantages of the ground-station system according to the
invention are the ability of one particular operator to create a
so-called "global image" because a user of a mobile station can now
manage with one ground-station identification code over the entire
world and, to be specific, according to one standard procedure
instead of a different standard procedure for each ground station.
In addition, the ground-station system according to the invention
offers an operator the possibility of providing a user with the
same possibilities over the entire world, even in areas which were
hitherto regarded as being territories of other operators, which
will promote competition and will considerably reduce the
dependence of an operator on other operators.
It should be pointed out that the possibilities also include, of
course, also providing the first ground station with a further
second processing arrangement so that satellite signals, comprising
identification codes of the second type, such as, for example,
ground-station identification codes of the second type, can also be
processed at the site of the first ground station before they are
transmitted via the first link. A disadvantage of this is the
additional costs of the further second processing arrangement. It
should, furthermore, be pointed out that, although known ground
stations detect the ground-station identification codes associated
with satellite signals, they do so only for the purpose of
determining whether the satellite signals should be examined more
closely or should be ignored. On the other hand, ground-stations
according to the invention detect the ground-station identification
codes associated with satellite signals for the purpose of
determining whether the satellite signals should be processed or
should be transmitted to other ground stations without processing.
From this there emerges yet a further advantage of the
ground-station system according to the invention, which makes use
of the aerials of the ground stations in a more efficient way.
The ground-station system according to the invention, furthermore,
offers at least two possibilities. Firstly, the identification code
could correspond to the ground-station identification code, as
already proposed above, and such as, for example, a LESID (local
earth station identification code), in which case the user of a
mobile station no longer needs to be acquainted with the
information about the ground station via which communication should
take place because such a user could then use the same
ground-station identification code everywhere in the world. In that
case, if the user is situated with his mobile station, for example,
within the range of the first and/or the second satellite (which
first and second satellite can contact only the first ground
station situated in the first country), consequently he can now
generate the first satellite signal, comprising the second
ground-station identification code, in which case the first ground
station responds to the first satellite signal after detecting the
second ground-station identification code and in which case the
first satellite signal is not processed via the first processing
arrangement of the first ground station, but is only transmitted by
the first ground station via the first link to the second
processing arrangement of the second ground station in order to be
processed subsequently by the second processing arrangement at the
site of the second ground station. Secondly, the identification
code could correspond to a mobile-station identification code, such
as, for example, a MESID (mobile earth station identification
code), in which case the user of a mobile station may still have to
generate the correct ground-station identification code, but the
desired ground station (and the desired processing arrangement
associated therewith) is then selected on the basis of the
mobile-station identification code. In this case, if the user is
situated with his mobile station, for example, within the range of
the first and/or the second satellite, consequently he can now
generate the first satellite signal, which may comprise the first
ground-station identification code and always comprises a second
mobile-station identification code, in which case the first ground
station responds to the first satellite signal after detecting the
second mobile-station identification code and in which case the
first satellite signal is not processed via the first processing
arrangement of the first ground station, but is only transmitted by
the first ground station via the first link to the second
processing arrangement of the second ground station in order to be
processed subsequently by the second processing arrangement at the
site of the second ground station. Although a user of a mobile
station may now therefore no longer be able to manage with one
ground-station identification code over the entire world, he is
still able to do so according to one standard procedure instead of
a different standard procedure for each ground station. This second
possibility (which will be chosen, for example, if a satellite
controller does not agree to, or does not agree to in the interim,
the first possibility) requires, for example, reference to a first
internal table of the first ground station, a first portion of
which first internal table is regularly updated, for example, via a
network-coordinating station and a second portion of which first
internal table can be loaded by an operator or a user of a mobile
station with the required information, or requires, for example,
reference by the first ground station to a first external table
which is situated, for example, in the network-coordinating
station. Such first tables have, for example, a left-hand column
(for example the first portion) containing mobile-station
identification codes and a right-hand column (for example the
second portion) containing corresponding ground-station
identification codes or operator codes. It goes without saying that
both possibilities could also be combined, for example, by dealing
with satellite signals originating from the first and second
satellites in accordance with the first possibility and, for
example, by dealing with signals originating from the third
satellite (which third satellite can contact both the first ground
station situated in the first country and the second ground station
situated in the second country) in accordance with the second
possibility. Furthermore, both possibilities could be combined, for
example, by dealing with satellite signals originating from the
first and second satellites in accordance with the first and/or the
second possibility and, for example, by dealing with signals
originating from the third satellite in accordance with the
procedure already known.
A first embodiment of the ground-station system according to the
invention has the characteristic that the first satellite signal
comprises a destination code, the first ground station being
provided with
a further first detection arrangement for detecting the destination
code,
a further first through-coupling arrangement for through-coupling
the first aerial to the first processing arrangement in response to
a destination code of a first type and for through-coupling the
first aerial to the further second input of the second processing
arrangement via the first link in response to a destination code of
a second type.
By providing the first ground station with the further first
detection arrangement which detects the destination code associated
with the first satellite signal and with the further first
through-coupling arrangement which through-couples the first aerial
to the first processing arrangement in response to the destination
code of the first type and which through-couples the first aerial
to the further second input of the second processing arrangement
via the first link in response to the destination code of the
second type, the result is achieved that the first ground station
first of all investigates which further user the first satellite
signal is destined for before the first satellite signal is
processed or transmitted. This includes destination codes of the
first type, for example, in the case of users having mobile
stations who are situated within the range of the first ground
station and it includes destination codes of the second type, for
example, in the case of users having mobile stations who are
situated outside the range of the first ground station. As a
consequence of this, first satellite signals comprising
identification codes of the second type and comprising destination
codes of the first type are not actually transmitted via the first
link to the second processing arrangement, but, on the contrary,
are actually processed by the first processing arrangement. This
has the advantage that traffic between two users of mobile stations
who are both situated within the range of the first ground station,
but whose calling user generates the identification code of the
second type associated with the second ground station is actually
processed at the site of the first ground station, which avoids
excessive to-and-fro traffic via links.
Destination codes of the first type could also be associated, for
example, with fixed terminals which are connected to a fixed
terrestrial network and which are situated nearer the first ground
station, and destination codes of the second type could be
associated, for example, with fixed terminals which are connected
to a fixed terrestrial network and which are situated nearer the
second ground station. As a consequence of this, first satellite
signals comprising identification codes of the second type and
comprising destination codes of the first type are not actually
transmitted via the first link to the second processing
arrangement, but, on the contrary, are actually processed by the
first processing arrangement. This has the advantage that traffic
between a user of a mobile station and a fixed terminal situated
nearer the first ground station is actually processed at the site
of the first ground station, while the calling user generates the
identification code of the second type associated with the second
ground station, which avoids excessive to-and-fro traffic via
links.
In this case, the destination code is detected by the further first
detection arrangement of the first ground station, for example, by
reference to a second internal table of the first ground station,
which second internal table is regularly updated, for example, via
the network-coordinating station, or, for example, by reference to
a second external table by the first ground station, which second
external table is situated, for example, in the
network-coordinating station.
Preferably, the first ground station will detect destination codes
associated with first satellite signals transmitted via the first
satellite and destination codes associated with second satellite
signals transmitted via the second satellite, and the second ground
station will detect destination codes associated with fourth
satellite signals transmitted via the fourth satellite. As regards
third satellite signals to be transmitted via the third satellite
which are either transmitted to the first ground station or to the
second ground station, there is, of course, the advantageous
possibility of allowing both ground stations to detect the
destination codes, although, in this case, another advantageous
possibility could be not to do precisely this.
A second embodiment of the ground-station system according to the
invention has the characteristic that the second detection
arrangement is provided with a second through-coupling arrangement
for through-coupling the second aerial to the second processing
arrangement in response to an identification code of a second type
and for through-coupling the second aerial to a further first input
of the first processing arrangement via a second link in response
to an identification code of a first type.
By providing the second detection arrangement with the second
through-coupling arrangement which through-couples the second
aerial to the second processing arrangement in response to the
identification code of the second type and which through-couples
the second aerial to the further first input of the first
processing arrangement via the second link in response to the
identification code of the first type, the result is achieved that,
if the second ground station responds to second satellite signals
comprising the identification code of the second type (such as, for
example, the ground-station identification code of the second
type), the second satellite signals are consequently actually
processed via the second processing arrangement of the second
ground station, whereas, if the second ground station responds to
second satellite signals comprising the identification code of the
first type (such as, for example, the ground-station identification
code of the first type), the second satellite signals are not
processed via the second processing arrangement of said second
ground station, but are only transmitted by the second ground
station via the second link to the first processing arrangement of
the first ground station in order to be processed subsequently by
the first processing arrangement at the site of the first ground
station. In this case, the second link between the first ground
station and the second ground station is a communication connection
which can be formed, for example, by means of copper connections
and/or glass-fibre connections and/or satellite connections and/or
terrestrial radio connections.
A third embodiment of the ground-station system according to the
invention has the characteristic that the second satellite signal
comprises a destination code, the second ground station being
provided with
a further second detection arrangement for detecting the
destination code,
a further second through-coupling arrangement for through-coupling
the second aerial to the second processing arrangement in response
to a destination code of a first type and for through-coupling the
second aerial to the further second input of the first processing
arrangement via the second link in response to a destination code
of a second type.
By providing the second ground station with the further second
detection arrangement which detects the destination code associated
with the second satellite signal, and with the further second
through-coupling arrangement which through-couples the second
aerial to the second processing arrangement in response to the
destination code of the first type and which through-couples the
second aerial to the further second input of the first processing
arrangement via the second link in response to the destination code
of the second type, the result is achieved that the second ground
station first of all investigates which further user the second
satellite signal is destined for before the second satellite signal
is processed or is transmitted. In this case, destination codes of
the first type are associated, for example, with users having
mobile stations who are situated within the range of the second
ground station and destination codes of the second type are
associated, for example, with users having mobile stations who are
situated outside the range of the second ground station. As a
consequence of this, second satellite signals, comprising
identification codes of the first type and comprising destination
codes of the first type, are not actually transmitted via the
second link to the first processing arrangement, but, on the
contrary, are actually processed by the second processing
arrangement. This has the advantage that traffic between two users
of mobile stations who are both situated within the range of the
second ground station, but whose calling user generates the
identification code of the first type associated with the first
ground station is actually processed at the site of the second
ground station, which avoids excessive to-and-fro traffic via
links. In this case, the destination code is detected by the
further second detection arrangement of the second ground station,
for example, by
reference to a third internal table of the second ground station,
of which third internal table a first portion is regularly updated,
for example, via the network-coordinating station and of which
third internal table a second portion can be loaded with the
required information, for example, by an operator or a user of a
mobile station, or for example, by reference to a third external
table by the second ground station, which third external table is
situated, for example, in the network-coordinating station.
It goes without saying that the internal tables present in a ground
station may coincide to a greater or lesser degree and the external
tables present in a network-coordinating station may coincide to a
greater or lesser degree.
The invention, furthermore, relates to a ground station for use in
a ground-station system and provided with
at least one aerial for the reception of a satellite signal
comprising an identification code,
a processing arrangement comprising an input, coupled to the
aerial, for the reception and processing of the satellite signal
and comprising an output for the generation of a first outgoing
signal, and
a detection arrangement for detecting the identification code.
The ground station according to the invention has the
characteristic that the detection arrangement is provided with a
through-coupling arrangement for through-coupling the aerial to the
processing arrangement in response to an identification code of a
first type and for through-coupling the aerial to a link coupled to
a further ground station for feeding at least one portion of the
satellite signal to the further ground station in response to an
identification code of a second type.
A first embodiment of the ground station according to the invention
has the characteristic that the satellite signal comprises a
destination code, the ground station being provided with
a further detection arrangement for detecting the destination
code,
a further through-coupling arrangement for through-coupling the
aerial to the processing arrangement in response to a destination
code of a first type and for through-coupling the aerial to the
link coupled to the further ground station in response to a
destination code of a second type.
The invention, furthermore, relates to a device for use in a ground
station provided with an aerial for the reception of a satellite
signal comprising an identification code, which device is provided
with
a processing arrangement comprising an input which can be coupled
to the aerial for the reception and processing of the satellite
signal and comprising an output for the generation of a first
outgoing signal, and
a detection arrangement for detecting the identification code.
The device according to the invention has the characteristic that
the detection arrangement is provided with a through-coupling
arrangement for through-coupling the aerial to the processing
arrangement in response to an identification code of a first type
and for through-coupling the aerial to a link coupled to a further
ground station for feeding at least a portion of the satellite
signal to said further ground station in response to an
identification code of a second type.
A first embodiment of the device according to the invention has the
characteristic that the satellite signal comprises a destination
code, the device being provided with
a further detection arrangement for detecting the destination code,
and
a further through-coupling arrangement for through-coupling the
aerial to the processing arrangement in response to a destination
code of a first type and for through-coupling the aerial to the
link coupled to the further ground station in response to a
destination code of a second type.
The invention also relates, furthermore, to a method for processing
a satellite signal originating from a satellite by a ground
station, which method comprises the steps of
the reception of the satellite signal comprising an identification
code via an aerial of the ground station,
the feeding of the satellite signal to a processing arrangement of
the ground station,
the processing of the satellite signal by the processing
arrangement of the ground station and generation of a first
outgoing signal, and
the detection of the identification code by a detection arrangement
of the ground station.
The method according to the invention has the characteristic that
the method comprises the steps of
the through-coupling of the aerial of the ground station to the
processing arrangement of the ground station in order to process
the satellite signal via the processing arrangement of the ground
station in response to an identification code of a first type,
and
the through-coupling of the aerial of the ground station to a link
coupled to a further ground station for feeding at least a portion
of the satellite signal to the further ground station in order to
process at least the portion of the satellite signal via a further
processing arrangement of the further ground station in response to
an identification code of a second type.
A first embodiment of the method according to the invention has the
characteristic that the method comprises the steps of
the detection of a destination code associated with the satellite
signal by a further detection arrangement of the ground
station,
the through-coupling of the aerial of the ground station to the
processing arrangement of the ground station in order to process
the satellite signal via the processing arrangement of the ground
station in response to a destination code of a first type, and
the through-coupling of the aerial of the ground station to the
link coupled to the further ground station for feeding at least the
portion of the satellite signal to said further ground station in
order to process at least the portion of the satellite signal via
the further processing arrangement of the further ground station in
response to a destination code of a second type.
From WO 92/19050 a global satellite communication system with
geographic protocol conversion is known. This document
substantially discloses the transmitting of messages to mobile
users. Therefore, the invention relating to the transmitting of
signals from a mobile user via a satellite to a ground station is
not known from this document.
From GB 2 275588 a global satellite communication system is known.
In order to determine and register the location of a mobile
terminal, the mobile terminal transmits an identification signal,
indicating the satellite or the ground station via which it may be
reached. This information is stored in data storage means. When a
call for the mobile terminal comes in, the information is used to
route the call, correctly.
References
WO 92/19050
WO 92/00636
GB 2 275588
All references are deemed to have been incorporated in this patent
application.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be explained in greater detail by reference to
an exemplary embodiment shown in the figure. In the figure:
FIG. 1 shows a ground station according to the invention for which
is coupled via a control connection 34 to a control input/output of
modulator 14. An output of demodulator 12 is coupled via a
connection 21 to an input of a device 10, a first output of which
can be coupled via a connection 25 to a terrestrial network not
shown in FIG. 1 and a second output of which is coupled via a
connection 28 to an input of modulator 14 and a link input of which
can be coupled via link 26 to another ground station not shown in
FIG. 1 and a link output of which can be coupled via a link 27 to
the other ground station not shown in FIG. 1 and a first or second
or third control input/output of which is coupled via a control
connection 31 or 32 or 33, respectively, to processor 13.
Device 10 comprises a detection arrangement 4 and a processing
arrangement 3 and a switch 9. Detection arrangement 4 is provided
with an input which is coupled via connection 21 to the input of
device 10 and is provided with a first output which is coupled via
a connection 22 to a first input of processing arrangement 3 and is
provided with a second output which is coupled via link 27 to the
link output of device 10. A first or second control input/output of
detection arrangement 4 is coupled via connection 31 or 32,
respectively, to the first or second control input/output,
respectively, of device 10. A second input of processing
arrangement 3 is coupled via link 26 to the link input of device 10
and a control input/output is coupled via control connection 33 to
the third control input/output of device 10. An output of
processing arrangement 3 is coupled via a connection 24 to an input
of switch 9, a first output of which is coupled via connection 25
to the first output of device 10 and a second output of which is
coupled via connection 28 to the second output of device 10.
Detection arrangement 4 comprises a first detector 5, an input of
which is coupled via connection 21 to the input of detection
arrangement 4 and a control input/output of which is coupled via
connection 31 to the first control input/output of detection
arrangement 4, and comprises a second detector 7 which functions as
a further detection arrangement and an input of which is coupled
via connection 21 to the input of detection arrangement 4 and a
control input/output of which is coupled via connection 32 to the
second control input/output of detection arrangement 4. Detection
arrangement 4, furthermore, comprises a first changeover switch 6
which is controlled by first detector 5 and functions as a
through-coupling arrangement and a main contact of which is coupled
via connection 21 to the input of detection arrangement 4 and a
first switch contact of which is coupled via connection 22 to the
first output of detection arrangement 4 and a second switch contact
of which is coupled via a connection 23 to a main contact of a
second changeover switch 8 which is controlled by second detector 7
and functions as a further through-coupling arrangement and a first
switch contact of which is coupled via connection 22 to the first
switch contact of first changeover switch 6 and to the first output
of detection arrangement 4 and a second switch contact of which is
coupled via link 27 to the second output of detection arrangement
4.
The operation of the ground station 1 according to the invention
which is shown in FIG. 1 and comprises the device 10 according to
the invention and which is for use in a ground-station system
according to the invention, which ground-station system is provided
with at least the ground station 1 and the other ground station not
shown in FIG. 1, is as follows. In this connection, it is assumed
that ground station 1 can communicate with a first, a second and a
third satellite and that the other ground station can communicate
with the third and a fourth satellite, satellite signals to be
transmitted via the first, second, third or fourth satellite being
referred to as first, second, third or fourth satellite signals,
respectively.
A first user who is situated with his mobile station within the
range of the first satellite generates, for example, a first
satellite signal comprising an identification code of a first type
and a destination code. Said first satellite signal is passed to
ground station 1, which forms the property of a first operator, by
the first satellite, after any necessary conversion. Said first
satellite signal is fed via aerial 2 to transceiver 11 which feeds
it via connection 20 to demodulator 12, transceiver 11 informing
processor 13 via control connection 35 and demodulator 12 informing
processor 13 via control connection 30 of the arrival of the first
satellite signal. Via connection 21, the demodulated first
satellite signal is fed from demodulator to the first detector 5
which is situated in detection arrangement 4 and which detects the
identification code of the first type, and to the second detector 7
which is situated in detection arrangement 4 and which detects the
destination code. Via control connection 31, first detector 5
informs processor 13 of the identification code of the first type,
and via control connection 32, second detector 7 informs processor
13 of the destination code. In response to the detection of the
identification code of the first type, first detector 5 controls
changeover switch 6 in such a way that the main contact is
connected through to the first switch contact, as a consequence of
which connection 21 is connected through to connection 22 and the
position of the changeover switch 8 controlled by second detector 7
in response to the detected destination code becomes of subordinate
importance. Via connection 22, the first satellite signal flows to
processing arrangement 3 which processes the first satellite
signal, such as, for example, a message-switched satellite signal.
Via control connection 33, processing arrangement 3 informs
processor 13 of this. The processed first satellite signal is then
fed via connection 24 to switch 9 which either detects the
destination code yet again or is informed about said destination
code via detector 7 and/or processor 13 and, in response thereto,
either feeds the processed first satellite signal via connection 25
to the terrestrial network for feeding to another user
characterized by the destination code or feeds the processed first
satellite signal via connection 28 to modulator 14. Via control
connection 35 modulator 14 informs processor 13 of this, after
which the modulated first satellite signal is fed via connection 29
to transceiver 11, which informs processor 13 of this via control
connection 35 and transmits the modulated first satellite signal
via aerial 2 to the first, second or third satellite for feeding to
another user characterized by the destination code. Because the
first user generates the first satellite signal comprising the
identification code of the first type, from which identification
code of the first type it is evident that said first user is a
subscriber of the first operator, said first satellite signal is
processed in ground station 1, only after which does feeding to the
other user take place. The identification code of the first type
is, for example, a ground-station identification code of the first
type, or operator code of the first type, or is, for example, a
mobile-station identification code of the first type, or an MESID
(mobile earth station identification code) of the first type.
A second user who is situated with his mobile station within the
range of the first satellite generates, for example, a first
satellite signal comprising an identification code of a second type
and a destination code of a second type. Said first satellite
signal is passed by the first satellite, after any necessary
conversion, to ground station 1, which forms the property of the
first operator. Via aerial 2, said first satellite signal is fed to
transceiver 11, which feeds it via connection 20 to demodulator 12,
transceiver 11 informing processor 13 via control connection 35 and
demodulator 12 informing processor 13 via control connection 30 of
the arrival of the first satellite signal. Via connection 21, the
demodulated first satellite signal is fed from demodulator to the
first detector 5 which is situated in detection arrangement 4 and
which detects the identification code of the second type, and to
the second detector 7 which is situated in detection arrangement 4
and which detects the destination code of the second type. Via
control connection 31, first detector 5 informs processor 13 of the
identification code of the second type, and via control connection
32, second detector 7 informs processor 13 of the destination code
of the second type. In response to the detection of the
identification code of the second type, first detector 5 sets
changeover switch 6 in such a way that the main contact is
connected through to the second switch contact, as a result of
which connection 21 is connected through to connection 23. In
response to the detection of the destination code of the second
type, second detector 7 sets changeover switch 8 in such a way that
the main contact is connected through to the second switch contact,
as a result of which connection 23 is connected through to link 27.
Via link 27, the first satellite signal, such as, for example, a
message-switched satellite signal, flows in the unprocessed state
to the other ground station, which forms the property of a
second
operator, where the first satellite signal is then processed on
site in order to feed it to another user characterized by the
destination code of the second type. Because the second user
generates the first satellite signal comprising the identification
code of the second type, from which identification code of the
second type it is evident that said second user is a subscriber of
the second operator, said first satellite signal is not processed
in ground station 1 but is transmitted in the unprocessed state to
the other ground station in order to be processed there on site,
only after which does feeding to the other user take place. The
identification code of the second type is, for example, a
ground-station identification code of the second type, or operator
code of the second type, or is, for example, a mobile-station
identification code of the second type, or an MESID (mobile earth
station identification code) of the second type.
A third user who is situated with his mobile station within the
range of the first satellite generates, for example, a first
satellite signal comprising an identification code of a second type
and a destination code of a first type. Said first satellite signal
is passed by the first satellite, after any necessary conversion,
to ground station 1, which forms the property of the first
operator. Via aerial 2, said first satellite signal is fed to
transceiver 11, which feeds it via connection 20 to demodulator 12,
transceiver 11 informing processor 13 via control connection 35 and
demodulator 12 informing processor 13 via control connection 30 of
the arrival of the first satellite signal. Via connection 21, the
demodulated first satellite signal is fed from demodulator to the
first detector 5 which is situated in detection arrangement 4 and
which detects the identification code of the second type and to the
second detector 7 which is situated in detection arrangement 4 and
which detects the destination code of the first type. Via control
connection 31, first detector 5 informs processor 13 of the
identification code of the second type, and via control connection
32, second detector 7 informs processor 13 of the destination code
of the first type. In response to the detection of the
identification code of the second type, first detector 5 sets
changeover switch 6 in such a way that the main contact is
connected through to the second switch contact, as a result of
which connection 21 is connected through to connection 23. In
response to the detection of the destination code of the first
type, second detector 7 sets changeover switch 8 in such a way that
the main contact is connected through to the first switch contact,
as a result of which connection 23 is connected through to
connection 22. Via connection 22, the first satellite signal flows
to processing arrangement 3, which processes the first satellite
signal, such as, for example, a message-switched satellite signal.
Via control connection 33 processing arrangement 3 informs
processor 13 of this. The processed first satellite signal is then
fed via connection 24 to switch 9, which either detects the
destination code of the first type yet again or is informed via
second detector 7 and/or processor 13 of said destination code of
the first type and, in response thereto, feeds the processed first
satellite signal to modulator 14, for example, via connection 28.
Via control connection 35, modulator 14 informs processor 13 of
this, after which the modulated first satellite signal is fed via
connection 29 to transceiver 11, which informs processor 13 of this
via control connection 35 and which transmits the modulated first
satellite signal via aerial 2 to the first, second or third
satellite for feeding to another user characterized by the
destination code of the first type. While the third user generates
the first satellite signal comprising the identification code of
the second type, from which identification code of the second type
it is evident that said third user is a subscriber of the second
operator, said first satellite signal is not actually transmitted
in the unprocessed state to the other ground station in order to be
processed there on site, but the first satellite signal comprising
the identification code of the second type is actually processed in
ground station 1, after which feeding to the other user takes
place, because the destination code is of the first type, which
indicates that the other user is situated, for example, within the
range of the first or the second satellite.
If the identification code is a ground-station identification code
or operator code, first detector 5 can use said identification code
directly to set changeover switch 6. If the identification code is,
on the other hand, a mobile-station identification code, or an
MESID (mobile earth station identification code), a first table
should generally be referred to, of which first table a first
portion is regularly updated, for example, via a
network-coordinating station (NCS) and of which first table a
second portion can be loaded with the required information, for
example, by an operator or a user of a mobile station. Such first
tables have, for example, a left-hand column (for example, the
first portion) containing mobile-station identification codes and a
right-hand column (for example, the second portion) containing
corresponding ground-station identification codes or operator
codes. Such a first table may be situated in the ground station
itself as a so-called internal table (for example, as a component
of processor 13 in FIG. 1) or be situated in the NCS
(network-coordinating station) as a so-called external table, in
which case continuous communication does have to take place between
the ground station and the NCS. If a user of a mobile station
obtains access to the system, for example, via a first or second
predetermined number, a first or second ground-station
identification code or operator code, respectively, could be set by
the system automatically in response thereto. A user of a mobile
station can then also set a ground-station identification code or
operator code he desires himself, for example, via a predetermined
number and a unique code and pin code.
The destination code is, for example, a specific identification of
the other user, such as, in a first case, the telephone number of
the fixed terminal of the other user or, in a second case, the
number of the mobile station of said other user. A destination code
of a first type then implies, in the first case, that the telephone
number, or a portion thereof (such as a country code) relates to a
fixed terminal which is nearer ground station 1, and, in the second
case, it implies that the mobile station of the other user is
situated within the range of the first, second or third satellite.
A destination code of a second type then implies, in the first
case, that the telephone number or a portion thereof (such as a
country code) relates to a fixed terminal which is nearer the other
ground station, and, in the second case, it implies that the mobile
station of the other user is situated within the range of the third
or fourth satellite. Because users of mobile stations can move with
their mobile station, a second table will in general need to be
referred to, which second table has, for example, a left-hand
column containing numbers of mobile stations and telephone numbers
of fixed terminals and has a right-hand column containing
locations. In general, said location is stored automatically. Such
a second table may be situated in the ground station itself as a
so-called internal table (for example as a component of processor
13 in FIG. 1) or it is situated in the NCS (network-coordinating
station) as a so-called external table, in which case continuous
communication does have to take place between the ground station
and the NCS.
Instead of a table containing two columns (containing, for example,
identification codes or destination codes in the left-hand column
and, for example, ground-station identification codes or operator
codes or locations in the right-hand column) a table having only
one column (the left-hand column) could of course be used, in which
case it is then necessary to investigate whether, for example, an
identification code or a destination code is situated in said one
column or not, for example by confirming an equality or inequality,
and in which case if it is present (equality) a first operation
(for example, selection of a first ground-station identification
code or operator code or location) is then subsequently carried out
and, if it is absent (inequality), a second operation (for example,
selection of a second ground-station identification code or
operator code or location) is carried out.
The detection arrangement 4 shown in FIG. 1 comprises first
detector 5 and the changeover switch 6, which functions as a
through-coupling arrangement, and it preferably comprises second
detector 7 and the second changeover switch 8, which functions as a
further through-coupling arrangement. Of course, the two changeover
switches 6 and 8 could also alternatively be seen separately from
the detection arrangement 4, in which case detection arrangement 4
comprises only first detector 5 and, preferably, second detector
7.
The transceiver 11 demodulator 12 and modulator 14 shown in FIG. 1
will generally have more functions known to the person skilled in
the art than those which have hitherto been discussed. Thus,
satellite signals arriving via aerial 2 will be time-multiplexed
and/or frequency-multiplexed and they then have to be
demultiplexed, and signals to be sent via aerial 2 will have to be
time-multiplexed and/or frequency-multiplexed. In this connection,
identification codes and destination codes can be indicated both by
means of, for example, a header and by means of a predetermined,
defined location. Furthermore, a portion of the signal content of
satellite signals arriving via aerial 2 will be destined for
processor 13, and another portion will be destined for device 10,
and a portion of a signal content arriving via connection 28 at
modulator 14 will generally have to be combined with another
portion of a signal content arriving via control connection 34 at
modulator 14.
Given the above, it will be clear that, for each ground station,
device 10, transceiver 11, demodulator 12 and modulator 14 will
have to be implemented, for example, in duplicate, triplicate,
quadruplicate or quintuplicate, and that aerial 2 is implemented as
a separate transmitting aerial and receiving aerial. Of course, at
least one aerial is always present for each satellite to be
reached.
The links shown in FIG. 1 as an incoming link 26 and an outgoing
link 27 are communication connections which can be formed, for
example, by means of copper connections and/or glass-fibre
connections and/or satellite connections and/or terrestrial radio
connections. If the two respective links 26 and 27 are formed by
means of satellite connections, they will generally have to be
coupled to at least one of the devices 10 or at least one of the
modulators 14, respectively.
* * * * *